Precision Metric Gauge Block Set Designed for accurate dimensional calibration in labs, workshops, and inspection environments. Made from High-Speed Tool Steel Crafted from wear-resistant high-speed steel for excellent durability and long-term stability. Precision Ground to Tight Tolerances Blocks are mirror-lapped and manufactured to ISO 3650 standards for reliable wringing and minimal deviation. for Caliper and Micrometer Calibration for verifying and adjusting measuring tools like calipers, micrometers, and dial indicators. Protective Storage Case Included Comes in a foam-lined case for organized storage, safe transport, and quick access during setup tasks., Manufacturer: ZKLGS